18x2 +12x -6 = 0
ax2 bx c = 0
a = 18
b = 12
c = -6
Δ = b2-4ac
Δ = 12² - (4 * 18 * -6)
Δ = 144 - (4*-108)
Δ = 144 - (-432)
Δ = 576 Δ > 0
18x2+12x-6=0
x = -b ∓ √Δ 2a
x' = -12 - √576 2*18 = -12 - 24.0 36 = -36.0 36 = -1.0
x" = -12 + √576 2*18 = -12 + 24.0 36 = 12.0 36 = 0.333333333333
x' = -324.0
x" = 108.0
S = {x ∈ R / x' = -324.0, x" = 108.0 }